#include <time.h>
#include <pthread.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>

int getdate_err;

struct tm *getdate(const char *s)
{
    static struct tm tmbuf;
    struct tm *ret = 0;
    char *datemsk = getenv("DATEMSK");
    FILE *f = 0;
    char fmt[100], *p;
    int cs;

    pthread_setcancelstate(PTHREAD_CANCEL_DEFERRED, &cs);

    if (!datemsk) {
        getdate_err = 1;
        goto out;
    }

    f = fopen(datemsk, "rbe");
    if (!f) {
        if (errno == ENOMEM) getdate_err = 6;
        else getdate_err = 2;
        goto out;
    }

    while (fgets(fmt, sizeof fmt, f)) {
        p = strptime(s, fmt, &tmbuf);
        if (p && !*p) {
            ret = &tmbuf;
            goto out;
        }
    }

    if (ferror(f)) getdate_err = 5;
    else getdate_err = 7;
out:
    if (f) fclose(f);
    pthread_setcancelstate(cs, 0);
    return ret;
}
